As a gas circuit breaker used for a high-voltage power system, a so-called puffer-type gas circuit breaker is generally used, which breaks electric current by using pressure increase of an extinguishing gas during an opening operation and by blowing a compressed gas to an arc generated between electrodes.
In order to improve circuit-breaking performance of the puffer-type gas circuit breaker, a double motion system in which an electrode on a driven side which has been fixed in related art is driven in an opposite direction of a driving direction of a drive-side electrode is proposed.
For example, a system using a fork-shaped lever is proposed in Patent Literature 1. In this invention, the fork-shaped lever rotates when a pin interlocked with the movement on a drive side touches a recess of the fork, and the rotation is converted into a reciprocating motion in a direction of an opening/closing shaft, thereby driving a driven-side arcing contact in an opposite direction of the driving direction of the drive-side electrode. In a state where the pin is separated from the recess of the fork, the lever maintains the position and the driven-side arcing contact is stationary.
An object of the invention is to move the driven side efficiently with the minimum driving force in a time domain necessary for breaking electric current.
Moreover, a double motion system using a grooved cam is proposed in Patent Literature 2. In this system, a pin moves inside the grooved cam in accordance with the movement of a drive side, and the cam is rotated to thereby drive a driven side arcing contact coupled to the cam in an opposite side of a drive side electrode. A desired speed ratio between the driven-side arcing contact and the drive-side electrode can be realized by forming the grooved cam in an arbitrary shape.